Injector discharge control valve



Sept. 28, 1943.

B. E. FOLKE 2,330,275

INJECTOR DISCHARGE CONTROL VALVE Filed Sept. 25, 1942 BKNGT E. FOL K5 INVENTOR /mzwm ATTORNEY Patented Sept. 28, 1943 UNlTED STATES ATENT OFFICE 2,3303% INJECTOR DISCHARGE CONTROL VALVE Bengt E. Folke, Mamaroneck, N. Y., assignor to Nathan Manufacturing Company, New

N. Y., a corporation of New York 7 York.

9" Claims.

This invention relates to steam injectors and particularly to novel means for controlling the pressure in the Water delivery pipe between the injector and the boiler check va ve.

As is well known in the art, a non-return check valve is usually provided in the injector delivery line and located close to the steam boiler into which the water is injected. The purpose of this boiler check valve is to prevent water returning from the boiler when the injector is at rest, As the injector is usually located at a lower level than the boilercheck valve and at some distance away from it, it is often advantageous to place an additional nonreturn check valve close to the injector, so as not to waste the water in the long pipe between the injector and the boiler. This additional non-return valve, usually known the injector delivery check, also serves as a supplementary boiler check valve, in case the main check valve does not seat properly. It also reduces the strain on the boiler check valve and on themjector when the injector is started and it prevents a considerable amount of air from entering the boiler every time the injector is started.

When a long delivery pipe is used between the injector and the boiler check valve, and the water in the pipe is held substantially at boiler pressure, a considerable force is required to overcome the inertia of the mass of water when the injector is started. j w

The object of this invention is to provide a means to relieve the pressure in the pipe between the injector and the boiler checkfvalve without draining the water from the pipe.

Another object is to provide a'slight fleiribility to the heavy mass of water in the delivery pipe by reducing the pressure of the water in the pipe to considerably below the boiler pressure.

A further object is to provide means whereby a leaking boiler check valve may be readily detected by the operator.

Still further objects will become apparent in the following specification and in the drawing in which a preferred embodiment of the inven-' tion is shown.

In the drawing,

Fig. 1 shows a front elevatio-nal view of an injector, partly in section, and a diagrammatical view of the injector piping, as well as fragmentary sectional, diagrammatical views of the boiler and its check valve;

Fig. 2 shows a fragmentary sectional view, partly in elevation, through the injector delivery end showing the delivery check valve;

Fig. .3 shows an enlarged fragmentary sectional view, of a supplementary relief va ve located in the delivery check valve, and

Fig. 4 shows a fragmentary sectional view, partly in elevation through the delivery end of an injector incorporating a modified form of the invention. V

Like characters of reference denote similar parts throughout the several views and the following specification. 1

Referring to Fig. 1, J!) is an injector provided witha water inlet at H, a steam inlet 'at i2 and a water delivery pipe at 13. A steam valve I' l is provided between a steam supply pipe l5 and the steam inlet l2 to control the admission of Water through inlet 1 l; A boiler check valve ll permits water to pass from delivery pipe 13 into a boiler l8.

The injector H1 is provided with a delivery nozzle IS, a deliverycheck valve 23 having a guide 2|, and a seat 22.

Referring now to Figs. 2 and 3, the delivery check valve 28 is provided with a passage 23 and a ball check valve 24. The check valve 24 is adapted to rest against a seat 25 and is urged against the'seat by a spring 26 held in place by a sprin'gstop 2'1.

Fig. 4' shows a modified form where thesupplementary check valve is separated from the delivery check valve 20. Inthis mod fied form; the ball check valve 24, the spring 26 an-d'the spring stop?! are located in a cage 28 screwed into a partition 29 separating the passages leading to and from the delivery check valve 25!.

Communication with the supplementary check valve 24is established by "a passage 30 located in the cage'28 and a passage 3! located in partition 29;

The operation is as follows: i

When the injector is started, water charged through the del very nozzle Ill under the delivery check valve 2i), raising this check valve from. its seat 22. The water entering through delivery check valve 28 into the discharge pipe I3 raises the pressure in this pipe until it is sufficient to open the boiler check valve H and permit the water to be injected into the boiler l8.

When the injector is shut Oif th'e pressure in the-delivery nozzle I9 is suddenly reduced, permitting the, pressure in pipe 13 to close the de-' liverycheck valve 20. A slight reduction in the pressure, in pipe l3 will also permitthe boiler is disthrough the passage 23 unseats the supplementary ball check valve 24, compressing spring 25, permitting the pressure in pipe l3 to drop until it is balanced by the spring 26, when the ball check valve 24 will again rest against its seat 25. The tension of spring 26 is regulated so that it will permit a substantial drop in the pressure in pipe 13 but will close before the pressure is entirely dissipated and before the water is emptied from the pipe.

So, for instance, if the pressure in the water delivery pipe when the injector has been stopped, should be 250 lbs., this pressure will open the supplemental check valve against the atmospheric pressure in the injector body and permit the pressure in the water delivery pipe to be dissipated therethrough to that of the spring in the supplemental check valve which is usually set at 20 lbs. The loss of water to reduce the pressure to that point is negligible. The pressure in the Water delivery pipe which will then be only 20 lbs. reduces the load upon the injector when starting and so greatly facilitates the Prompt starting of the instrument.

Should the main boiler check valve be leaking, water from the boiler passing through the leaky check into the injector delivery pipe would be under a pressure much higher, even if dissipated to some extent, than the spring tension in the supplemental check valve and would be discharged through the overflow of the injector continuously while there is pressure on the boiler, serving as an indicator of this faulty condition.

It is understood that various changes in form, proportions and minor details of construction may be resorted to without departing from the principles or sacrificing any of the advantages of the invention as defined in the appended claims.

What I claim as new, is:

In combination. a steam injector having a delivery end, a del very check valve at said end, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery check valve and said boiler check valve, a supplemental check valve in the delivery end of said injector controlling passages by-passing said injector delivery check valve, and tensioning means in said supplemental check valve, said supplemental check valve opening in a d rection opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest for relieving the pressure in said pipe to the pressure of said tensioning means.

' 2. In combination, a steam injector having a delivery end, a delivery check valve at said end, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery check valve and said boiler check valve, a supplemental check valve in the delivery end of said injector controlling passages by-passing said injector delivery check valve, and adjustable tensioning means in said supplemental check valve, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest for relieving into the injector the pressure in said pipe to the pressure of said tensioning means.

3. In combination, a steam injector having a delivery end, a delivery check valve at said end, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery check valve and said boiler check valve, a supplemental check valve in said delivery check valve, and

tensioning means in said supplemental check valve, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest for relieving the pressure in said pipe to the pressure of said tensioning means.

4. In combination, a steam injector having a delivery end, a delivery check valve at said end, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, and a supplemental check valve in said delivery check valve consisting of a valve member, a tensioning spring, and a spring stop, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest for relieving the pressure in said pipe to the pressure of said tensioning spring.

5. In combination, a steam injector having a delivery end, a delivery check valve at said end, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, a supplemental check valve in the delivery end of said injector controlling passages by-passing said injector delivery check valve and consisting of a cage containing a valve member, a tensioning spring, and a spring stop, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure insaid delivery pipe when the injector is at rest for relieving into the injector the pressure in said pipe to the pressure of said tensioning spring.

6. In combination, a steam injector having a delivery end, a partition in said end, a delivery check valve in said partition, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, a supplemental check valve in said partition controlling passages therethrough, and tensioning means in said supplemental check valve, said supplemental check valve adapted to be opened by pressure in said delivery pipe when the injector is at rest for relieving the pressure in said pipe to the pressure of said tensioning means.

'7. In combination, a steam injector having a delivery end, a partition in said end, a delivery check valve in said partition, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, a supplemental check valve in said partition controlling passages therethrough, and adjustable tensioning means in said supplemental check valve, said supplemental check valve adapted to be opened by pressure in said delivery pipe when the injector is at rest for relieving into the injector the pressure in said pipe to the pressure of said tensioning means.

8. In combination, a steam injector having a delivery end, a partition in said end, a delivery check valve in said partition, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, a supplemental check valve in said partition consisting of a cage containing a valve member, a tensioning spring, and a spring stop, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest for relieving the pressure in said pipe to the pressure of said tensioning spring.

9. In combination, a steam injector having a delivery end, a partition in said end, a delivery check valve in said partition, a steam boiler, a boiler check valve at said boiler, a water delivery pipe between said delivery end and said boiler check valve, a cage through said partition, a supplemental check valve in said cage controlling pasages therethrough, and tensioning means in said supplemental check valve, said supplemental check valve opening in a direction opposite to that of said delivery check valve by pressure in said delivery pipe when the injector is at rest'for relieving into the injector the pressure in said pipe to the pressure of said tensioning means.

' BENGT E. FOLKE. 

